A sublimation transfer printer is a computer printer which employs a printing process that uses heat to transfer a sublimation ink from a carrier onto substrate materials such as a plastic, card, paper, or fabric. Dye sublimation inks, also known as disperse dye inks, are made of high purity and ultra-fine particle disperse dyes that can change from solid to gas without entering liquid phase. Sublimation printing is a process carried out more and more by inkjet printers with sublimation inks and sublimation papers. In sublimation transfer printing, sublimation inks may be deposited onto sheets or rolls of “transfer” paper as carrier, through a piezoelectric print head. After the ink is deposited in the form of a negative image the transfer paper is placed on a heat press along with the substrate material (fabric). The heat press is then used to transfer the image onto the substrate material. Recommended transfer temperatures range from 180-230° C., with a transfer time of 30-60 seconds. When using thin fabrics as substrate, the temperature may be kept as low as 170° C.
As polyesters fibers and the weaving are constantly improved to match the comfort of the cotton fiber, the use of polyester in fast fashion and sportswear is rapidly growing. Shirts like the Nike Pro Core Compression consists of 90% polyester and 10% elasthan, and removes sweat from the body and keeps the runner cool. This reduces the need for cotton. Polyester fabric is printed mostly with sublimation ink. The great benefit of sublimation ink is the fact that the colorants will bond with the fiber during sublimation or fixation. The colors are ‘inside’ the fabric rather than on the surface as would be the case with screen printing and direct printing methods of reactive and acid dyes. Thus, the end result of the sublimation process is a nearly permanent, high resolution, full color print, which may be washed or steamed to remove any ink or other process residues. Separate fixation or finishing after the transfer step will not be required.
The main issue with sublimation transfer printing, however, is speed. Also for larger productions (greater surface or continuous printing) existing sublimation transfer printers are less suitable because of positioning errors and print to print color errors (which are hard to predict during printing as colors will only appear at the right shade after fixation). For large production cycles, using a multitude of printers and calenders may be an option. However, printer to printer and calender to calender output varies as the performance and quality of these devices vary. The inventors set out to solve these problems related to speed, or caused by a production set-up with a multitude of printers and calenders.